Liquids are commonly blended together in mechanical mixers of various designs which subject the liquids to violent agitation. Although this is an effective means for mixing most types of liquids, it is not practical to mix a gel with a liquid in this manner.
In a polymerization system which reacts a thin low viscosity monomer with a thick high viscosity concentrated polymer, it is necessary to obtain a uniform mixture quickly before appreciable reaction takes place. Thus the residence time in the mixer should be short, preferably involving a period of only minutes as opposed to typical mixers in polymerization systems which require a mixing time of tens of minutes or even hours. This is especially critical where polymerization reactants are mixed with recycled polymer in gel form. Care must be taken, however, not to degrade the polymer, which is a danger if the residence time is attempted to be shortened by making the mixing action too violent. Thus on the one hand, to slow the mixing action too much can result in too long a residence time in the mixer, while on the other hand to speed the action through increased agitation can be detrimental to the polymer.
It would therefore be highly desirable to be able to mix a gel with a liquid in a short period of time without degrading the gel.